Portion of a display screen with a graphical user interface



FIG. 1 is a front view of a portion of a display screen with a graphicaluser interface showing the new design;

FIG. 2 is a front view of a second embodiment thereof; and,

FIG. 3 is a front view of a third embodiment thereof.

The dashed lines showing text and images form no part of the claimeddesign. Said dashed lines, dashed image, and text are presented only forenvironmental purposes.

CLAIM The ornamental design for portion of a display screen with agraphical user interface, as shown and described.